Windows Presentation Foundation (WPF) and Silverlight provide developers with a simple, declarative means of quickly and easily delivering applications with rich user experiences. But as the number of moving parts increases, keeping the project under control becomes exponentially more difficult.

In the September 2008 issue of MSDN Magazine, Glenn Block explains what a composite application is and how the new Composite Application Guidance for WPF (formerly code-named "Prism") can help you build rich, maintainable apps.